Apple as early as next week will deliver a much-needed refresh to its iMac line of all-in-one desktops, adopting Intel's newest family of Core processors and the latest in personal computing I/O technology, AppleInsider has learned.

More specifically, people familiar with the matter say Apple plans to introduce the new models on Tuesday, May 3, swapping out the systems' first-gen Core i processors and miniDisplay ports for second-generation Core i chips and the company's new high-speed Thunderbolt port. However, rumors that 2011 would see changes to the iMacs' display panel size (1, 2) and the inclusion of 6000-series AMD Radeon HD chips, could not be confirmed with any degree of certainty.

In the days leading up to major product launches, Apple routinely makes certain requests of its various operating segments to assure the rollout goes as smoothly as possible. This week saw several of those measures put into place, according to those same people, who've continually provided accurate information when it comes the Mac maker's future plans.

In addition, people familiar with the Cupertino-based company's retail operations confirmed to AppleInsider that a "visual night" is similarly slated for the early morning hours of May 3rd. "So it is highly likely that whatever new product that is going to be refreshed or introduced will be done on [that day]," one of those people said.

These visual nights see several Apple retail employees in each location work throughout the evening and early a.m. hours, making significant modifications to the product layouts on the showroom floors, often removing previous generation products in favor of newly introduced models.

For Apple, next week's launch will mark the first time the company has refreshed its flagship desktop line in over 9 months. It also comes at a crucial time for the iMac —and Mac desktops in general —which are rapidly approaching an all-time low when it comes to their share of the Mac's product mix.

As Apple slowly transitions into a full-fledge mobile company, desktops have seen their share of Mac shipments slip into a slow but inevitable decline, falling from more than 50% of the company's Mac product shipments in the first quarter of 2006 to just 26% of the total units Mac units shipped during the second fiscal quarter of 2011 (see graph below).

As consumers increasingly grow accustomed to mobile computers, Apple faces a tall order in attempting to keep the desktop relevant in today's climate. As such, the company is said to be exploring designs that could shed as much as 50% off the footprint of future models by 2012, mirroring a pattern that's become evident in the big-screen TV market.

Thunderbolt iMacs are just the first of several Mac product refreshes Apple has planned for the months leading into and through this year's educational buying season. Versions of the company's hot-selling MacBook Airs are next to receive the Thunderbolt while adopting Intel's latest low-voltage Core i chips.